Need complete list of all 'key codes' for K1 Max Troubleshooting, Please. (Key526 not listed)

ISSUE: K1 Max fails bed leveling from Mainsail Web-UI Screen. Manual calibration from K1 Max touchscreen completes, but still rams print head into the side of the printer.

System:
K1 Max - rooted with 1.3.3.5 firmware installed. Mainsail interface used from web browser on Win10 PC. My K1 Max is a December 2023 build, no physical modifications have been made. Initial bed mesh calibration was error free. Use of K1 Max, to this point in time, has been error free.

Error messages:
{‘code’: ‘key526’, ‘msg’: ‘PR_ERR_CODE_HAVE_LOST_STEP: Z-axis motor step loss was found.’, ‘values’: [‘RUN_G29_Z check last point res_z:(6.637994318181832) out of lost_step_dis:0.5’]}
[RAISE_ERROR]{‘code’: ‘key526’, ‘msg’: ‘PR_ERR_CODE_HAVE_LOST_STEP: Z-axis motor step loss was found.’, ‘values’: [‘RUN_G29_Z check last point res_z:(6.637994318181832) out of lost_step_dis:0.5’]}

How it happened:
After months of light use, I decided to rerun the bed calibration because my PETG was starting to fail at the first layer after a few days of use. Today I used the bed mesh calibration from the Mainsail menu. In performing the last row of measurements at the very last point (left, rear), the print head slams into the corner. It does not do that for any other measurements of the left side. These two error messages appear in the dialog box and no new meshes have been created or saved. Subsequent bed mesh calibrations from the web UI fail in the same way. I do not have KAMP installed in the firmware.

I ran the bed mesh test from the touchscreen on the K1 Max. This time it completed without error but the print head still slammed into the rear left corner again. I had to type SAVE_CONFIG in the web UI to update the printer.cfg file with the latest bed mesh. Otherwise this mesh would have been lost when I turned off the printer.

I’ve read the blog post: https://store.creality.com/blog/creality-k1-max-fault-codes-list

But this list only details Key500 - Key508. It then skips to 2000. I hope someone from Creality sees this and can point me to the documentation which explain these error messages or can tell me what is happening. Thank you for reading.

Check error code 2526

^^^^^
This has been the bane of my existence for 2 weeks now!
I do a fair bit of tech-ing and trouble shooting, but can’t solve this! Rooted to find the issue and these are the exact errors I receive, numbers are slightly different.

I had KAMP, removed it, got it from a dif repository, on and on. I don’t think it’s the issue, I can post all my config files, but they look ok.
The problem is deeper. The nozzle is supposed to be an End Stop. Why is this failing?